InFactory-1.1 is an upgrade version from InFactory to support IndoorGML 1.1.

The main difference of IndoorGML 1.1 from the previous one (v.1.0.3) is the inclusion of "level" property of CellSpace. Since "level" property is an optional and cardinatity is [0..*], no conflict takes place with IndoorGML 1.0.3. The remaining part is exactly identical with the previous InFactory (https://github.com/STEMLab/InFactory)